So glad this came up when I searched for "Denver with teenager"! I had a very good time but my 15 year old son had the time of his life!
It was my first time rappelling, and guide Dan explained everything--it felt safe while also being adventurous. The views were gorgeous, too.
We stayed in Golden the rest of the day, with a great lunch and renting e-bikes. Definitely would have tried river tubing if we had brought our swimsuits, too. Great day all around! Definitely recommend!